In some field applications branch connections need to be formed to a main electrical line without disrupting or severing the main electrical line. This is particularly true with tracer wires as one oftentimes needs to attach a branch wire to a main wire to form an electrical connection therebetween without cutting the main wire. One of the difficulties in forming a mechanical wire connection between a main tracer wire and a branch tracer wire is that one needs to maintain the integrity of the wire connection during the subsequent handling of the wire connector. The handling of the wire connector prior to or during the burial of the branch wire may accidently pull the branch wire free from the main wire, which results in an open circuit. One of the types of connectors commonly used to form such mechanical electrical connections between insulation covered tracer wires and the like are insulation displacement connectors since they can simultaneously form an electrical connection between wires even though the insulation is not stripped from the wires.
The insulation displacement connectors, which are well known in the art, typically comprise a pair of cantilevered spaced apart blade members each having internal edges for penetrating through an outer insulation cover on a wire to bring the edges into electrical contact with the electrical wire. The insulation displacement connectors, which are often referred to as IDC connectors allow one to quickly form an electrical connection between insulation covered electrical wire and the blade members within the IDC connector without having to manually remove the insulation covering from the wire. The spacing of the blunt edges of the blade from each other are sized so that when an electrical wire with an insulation covering is forced between the blunt edges on the blades the blunt edges penetrate through the softer insulation covering to bring the blunt edge of the blades into electrical contact with the harder metal electrical wire. Typically, the spacing between the blades is wider at the top to facilitate insertion of the wire between the blades.
Examples of insulation displacement connectors can be found in the following U.S. patents.
U.S. Pat. No. 4,682,835, shows an IDC connector where the thickness of upper part of the blade is at a reduced dimensions compared to the lower section of the blade.
U.S. Pat. No. 4,826,449 shows a pair of blades that includes projections on the back edge of the blades to stiffen the blades and increase resistance to outward deformation of the blades during wire insertion at low temperatures.
U.S. Pat. No. 4,002,391 shows an IDC connector with a set of offset swages in the blades to cut the insulation from different sides as the wire is inserted between the blades.
U.S. Pat. No. 3,636,500 shows an IDC connector with that cut a square notch in the insulation through sharp corner edges on the blades that remain in place until engaged by the conducting wire.
U.S. Pat. No. 3,521,221 shows tapered edges on the blade so more than one size electrical wire can be inserted into electrical engagement with the blades.
U.S. Pat. No. 7,934,941 shows an IDC connector, which has a pair of covers that are folded together to clamp the electrical wire therebetween.
U.S. Pat. No. 7,458,840 shows a set of parallel blades that are connected together with different slot spacing between each of the blades. In one pair of blades there is a narrow slot located at the slot entrance of one pair of blades and a wide slot located at the bottom of the blades at the other pair of blades there is a wide slot located at the slot entrance and a narrow slot at the bottom of the slot.
U.S. publication 2016/0218444 shows an insulation displacement connector with dual blades for engaging the wires therein.
U.S. publication 2015/0288078 shows another example insulation displacement connector with levers for bringing the blades in the wire connector into engagement with the wires therein.
The examples of IDC connectors listed above reveal that a variety of insulation displacement connectors are available that allow one to form an electrical connection through an insulation covered wire without having to strip the insulation covering from the wire. Typically, one of the advantages of IDC connectors is that they can be used to connect a main wire line to a branch wire line without having to cut the main wire line, which makes them useful in applications such as tracer wire applications where a series of branch wire lines may be connected to a main wire line in order to provide an underground wire network that can later be located using above ground equipment. Typically, the tracer wires are placed along an underground pipeline when the pipeline is buried so that one can later detect the location of the underground pipeline with above ground equipment through the sensing the presence of the underground tracer wires. In most cases the main underground pipeline includes branch underground pipelines, which also need to be identified through placement of tracer wires along the branch lines. To identify both the main pipeline and the branch pipeline a branch tracer wire, which extends along a branch pipeline is connected to the main tracer wire that extends along the main pipeline, preferably without severing the tracer wire that extends along the main pipeline. The simultaneous formation of the electrical connection and the removal of the insulation on the branch line wire and the main line wire, which occurs in one step is a time saving field benefit. However, unless care is taken in handling the IDC connector the electrical connection formed therein may be disrupted during the subsequent handling of the IDC connector thus spoiling the electrical connection between the branch wire and the main wire. This is particularly true in cases where the IDC connector joining the main wire and the branch wire are buried underground since the forces generated on the wires during the process of burying the connector in the soil may unknowingly disrupt the electrical connection between the branch wire and the main wire. If the broken electrical connection is noticed, one must remove the connector from the soil and reform the electrical connection therein and then rebury the connector in the soil. On the other hand, if the broken electrical wire connection is not noticed a future operator may not be able to detect or locate the underground branch pipeline, which may lead to disastrous results since an operator digging in the area may accidently rupture the branch pipeline, for example with a backhoe shovel or the like, which can cause an explosion or at the least cause an environmental disastrous as the contents of the branch pipeline are released into the environment.